1. Field of the Invention
This invention relates generally to beverage dispensers of the type adapted to be carried on the back of a vendor, and more particularly to a portable back pack beverage dispensing system including a dispensing tank having an insulated flexible jacket and a gas pressurizing member connected to the tank for maintaining gas pressure on the beverage.
2. Brief Description of the Prior Art
Portable beverage dispensers adapted to be transported on the back of a vendor by use of a body harness are known, as disclosed by way of example, in Charpiat U.S. Pat. No. 2,684,787 and Grafia U.S. Pat. No. 2,808,965 et al. Such portable dispensers include a tank made of rigid material enclosing a liquid storing chamber from which the beverage is dispensed and into which the beverage is charged through a reloading valve connected to the bottom of the tank. The beverage is accordingly dispensed under a gravitational pressure head. To assist in dispensing of the beverage, particularly when the liquid within the tank becomes depleted, the tank chamber may be internally pressurized with air by means of a pump as disclosed, for example, in Dolgin U.S. Pat. No. 3,147,889.
Motsenbocker, U.S. Pat. No. 4,420,097 discloses a portable liquid dispenser having an insulated carring case which contains a first flexible container and a second flexible container positioned therein. A freezable liquid is contained in the second container and the liquid to be dispensed is contained in the first container in contact with the surface of the container with the frozen liquid to cool the liquid to be dispensed. The liquid is dispensed under gravitational pressure.
Boxer et al, U.S. Pat. No. 4,526,298 discloses a flexible water bag or pouch which may be insulated that is carried on shoulder straps similar to a back pack. The liquid is dispensed by a squeeze type dispensing nozzle.
Ash, U.S. Pat. No. 4,896,402 discloses a rigid dispenser tank with an outer insulated jacket and an interior flexible bladder connected to a hand pump. Liquid to be dispensed is stored in the rigid dispenser tank and the flexible bladder is inflated to maintain the liquid under pressure.
Sims, U.S. Pat. No. 3,662,929 discloses a non-insulated rigid container with interior flexible bladder connected to a source of fluid pressure. A fluid substance to be dispensed is stored in the rigid container and the flexible bladder is inflated to discharge the fluid substance under pressure.
Uhlig, U.S. Pat. No. 4,098,434 discloses a non-insulated fluid product dispenser having first container and a second flexible container positioned inside the first container. Fluid to be dispensed is contained in one of the containers and fluid under pressure is introduced into the other container to urge the product fluid through a dispensing nozzle or opening.
Cornelius, U.S. Pat. No. 2,513,455 discloses a non-insulated rigid dispenser tank with an interior flexible bladder connected to a gas container. Fluid to be dispensed is stored in the rigid dispenser tank. The gas fed to the bladder condenses at the pressure and temperature at which the fluid in the container is to be discharged.
Shy, U.S. Pat. No. 4,300,705 discloses a compressed vacuum insulated bottle which operates by siphonage and compression of an elastic pouch in the top of the bottle stopper to siphon boiling water into the elastic pouch and then to drain off the boiling water by compression.
Beverage dispensers using internal pressurization of the beverage containing tank promote deterioration of internal tank surface so as to limit tank construction to expensive materials, such as stainless steel. Internal pressurization of the beverage tank has also been known to cause, to some extent, degradation in the quality of the beverage, such as loss of carbonation. For obvious health reasons, metal beverage tanks also must be repeatedly and thoroughly cleaned.
The present invention is distinguished over the prior art in general, and these patents in particular by a portable beverage dispenser system housed within a rigid back pack and transported on the back of a vendor. A beverage dispensing container, dispensing hose, and a pressurized gas container is housed within the back pack. The beverage dispensing container has a rigid wall surrounded by a flexible thermally insulating and cushioning jacket and an access opening at the top end of the dispensing container receives a removable flexible liner. A releasably locked closure lid is removably mounted within the access opening and has a gas fill valve and liquid fill and dispensing valve thereon with passages extending through the closure. The flexible liner is inserted into and withdrawn from the dispensing container in a collapsed condition and substantially conforms to the shape of the interior of the container in an installed liquid filled condition. The liner has an open end releasably engaged on the lid closure and forms a fluid pressure sealed envelope for containing the liquid beverage and the pressurized gas. The pressurized gas container is connected to the gas fill valve to maintain pressurization of the liquid in the dispensing container, and the dispensing hose is connected at one end to the liquid fill and dispensing valve and has a manually operable dispensing valve at the other end for dispensing the pressurized liquid.